Beowulf is the oldest surviving piece of English literature from the Middle Ages. The only surviving manuscript, which you can see above, is housed in the British Library in London. This manuscript was produced somewhere between 975 and 1025 AD, but the story itself is much older, probably dating back to the 6th or 7th century AD.
It is an epic poem with lots of violence, mythical monsters, impressive heroes, swanky weapons and bloody revenge. It tells the life story of Beowulf, a heroic warrior.
When the poem was written down, it was already an old story. It had probably been told around campfires or in the halls of kings and noblemen for centuries. Mostly these were told by professional storytellers, scops, who memorised the stories and told (or rather, performed) them. They would pass on their stories from one generations of scops to the next: this is called the oral tradition. An important literary technique used to help scops memorise the poems, which we also see in Beowulf, is alliteration. This is when many words within a line start with the same sound.
Beowulf is written in English, but hardly recognisable as such. We call this variety of the language Old English or Anglo-Saxon and it is derived from the Germanic languages. After the fall of the Roman Empire, there was unrest in western Europe and some tribes started moving or expanding their territories during what is known as the Migration Period. The Germanic tribes of the Angles, Saxons, Jutes and Frisians moved from their original home countries in the Low Countries, Germany and Denmark, to the British islands, driving back the Roman Britons and the Celts who were living there.
Old English is so old that it sounds like a completely different language. Watch the video below for a sample of the opening lines, read out in Old English.